Field of the Invention
The invention relates to an optical lens, and particularly relates to an optical lens assembly.
Description of Related Art
In recent years, as use of portable electronic devices (e.g., mobile phones and digital cameras, etc.) becomes ubiquitous, techniques related to image modules have also been developed significantly, wherein the image module mainly includes an optical lens assembly, a module holder unit and a sensor, etc., and the demand for minimized image module increases due to a thinning and lightweight trend of mobile phones and digital cameras. As dimensions of a charged coupled device (CCD) and complementary metal-oxide semiconductor (CMOS) are reduced and significant progress is made in related technology, the length of the optical lens assembly in the image module is also required to be correspondingly reduced. However, in order to avoid decline of image capturing effect and image capturing quality, good optical performance should also be achieved while the total length of the optical lens assembly is shortened. The most important characteristics of the optical imaging lens are imaging quality and a volume thereof.
Specifications of portable electronic products change rapidly, and the optical lens assemblies serving as key components are also developed in diversified ways. Applications of the optical lens sets not only include image capturing and video recording, but also include environment monitoring, driving data recording, etc., and along with progress of image sensing technology, consumers have higher demand on imaging quality. Therefore, the design of the optical lens assemblies not only requires achieving good imaging quality and a smaller lens space, but also has to be considered improvement of field of view and the size of an aperture due to a dynamic and light inadequate environment.
However, regarding the design of the optical lens assemblies, in order to fabricate the optical lens assemblies with both characteristics of good imaging quality and miniaturization, it is not enough to purely scale down the lenses with good imaging quality, and a material property is also involved, and practical problems in production such as an assembling yield, etc., are also considered.
A technical difficulty for fabricating the miniaturized lens is obviously higher than that of the conventional lens, so that it is still a target of the industry, government and academia to produce the optical lens assembly complied with demands of consumer electronics and to keep improving the imaging quality thereof.